This project is designed to measure and characterize a collagenolytic enzyme from a variety of head and neck tumors and to determine the significance of collagenolysis in the invasiveness and clinical behavior of these malignancies in humans and in an experimental epidermoid tumor in rats. Tumor collagenase will be purified and characterized both biochemically and immunologically. Collagenase from epithelial and connective tissue tumors will be compared to collagenase of normal skin, burn granulation tissue, epidermoid carcinoma cell cultures, and animal tumors in order to determine the pathogenicity source of the enzyme and enzyme control. This will be done by immunocytochemical localization and analysis of enzyme inhibitors and activators. Collagenase will be measured by radioimmunoassay and by collagen-lysing activity and compared with specific parameters of tumor invasiveness such as the ratio of surface area to depth of penetration, involvement of deep structures, and the presence of regional and distant metastases. Recurrence and survival rates in humans and animals after two years will be compared with the original collagenase levels. The animal model will be used to test whether collagenase inhibition with a specific antiserum will decrease tumor invasiveness and improve animal survival.